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1.
Braz. j. biol ; 83: e245585, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339413

RESUMO

Abstract Many soil microorganisms' i.e., bacteria and fungi produce secondary metabolites called antibiotics. These are used for the treatment of some of the bacterial, fungal and protozoal diseases of humans. There is a need for isolation of a broad spectrum of antibiotics from microorganisms due to the emergence of antibiotic resistance. In the present study two antibiotic producing bacteria Klebsiella pneumoniae and Bacillus cereus were isolated from pharmaceutical and poultry feed industry of Hattar, Haripur Pakistan. Total 10 waste samples were collected from different industries (Marble, Ghee, Soap, Mineral, Steel, Poultry Feed, Pharmaceutical, Qarshi, Cosmetic and Glass). Thirty-three bacterial strains were isolated from industrial wastes of these ten different industries. Fourteen out of thirty-three bacterial strains exhibited antimicrobial activities against at least one of the test microbes considered in this study including Escherchia coli, Staphylococcus aureus and Salmonella typhi. The bacteria were isolated by standard serial dilution spread plate technique. Morphological characterization of the isolates was done by Gram staining. Nine bacterial isolates out of fourteen were initially identified as B. cereus and five as K. pneumoniae through biochemical characterization. The antibacterial activities were tested by well diffusion method. Maximum number of antibiotic producing bacteria were isolated from pharmaceutical and poultry feed industry based on the results of primary screening, the most potential isolates S9, S19, S20, S22 and S23 were selected for secondary screening. The maximum activity against E. coli and S. aureus was recorded by bacterial isolate S19 i.e zones of inhibition of 6.5mm and 9mm while S20 showed 7.5mm and 6mm zones respectively. Molecular identification was carried out on the basis of 16S rRNA sequence analysis. Finally, the isolates were identified as B. cereus accession number LC538271and K. pneumoniae accession number MT078679. Analysis of bacterial extract S20 through GC-MS indicated the presence of 8 compounds of diverse nature and structure. Present study suggests that wastes of pharmaceutical and poultry feed industry may have antibiotic producing bacteria. These bacteria could be utilized for the production of antibiotics. B. cereus and K. pneumoniae isolated from wastes of poultry feed and pharmaceutical industries have the potential to produce antibiotics and could be used to control the microbial growth.


Resumo Muitos microrganismos do solo, ou seja, bactérias e fungos produzem metabólitos secundários chamados antibióticos. Eles são usados ​​para tratamento de algumas doenças bacterianas, fúngicas e protozoárias em humanos. Há necessidade de isolamento de um amplo espectro de antibióticos de microrganismos devido ao surgimento de resistência aos antibióticos. No presente estudo, duas bactérias produtoras de antibióticos, Klebsiella pneumoniae e Bacillus cereus, foram isoladas da indústria farmacêutica e de ração avícola de Hattar, Haripur, Paquistão. Um total de 10 amostras de resíduos foi coletado de diferentes indústrias (mármore, ghee, sabão, mineral, aço, ração para aves, farmacêutica, Qarshi, cosmética e vidro). Trinta e três cepas bacterianas foram isoladas de resíduos industriais dessas dez diferentes indústrias. Quatorze das 33 cepas bacterianas exibiram atividades antimicrobianas contra pelo menos um dos micróbios de teste considerados neste estudo, incluindo Escherchia coli, Staphylococcus aureus e Salmonella typhi. As bactérias foram isoladas pela técnica de placa de diluição em série padrão. A caracterização morfológica dos isolados foi feita por coloração de gram. Nove isolados bacterianos de 14 foram inicialmente identificados como B. cereus e cinco como K. pneumoniae por meio de caracterização bioquímica. As atividades antibacterianas foram testadas pelo método de difusão em poço. O número máximo de bactérias produtoras de antibióticos foi isolado da indústria farmacêutica e de ração avícola com base nos resultados da triagem primária, os isolados mais potenciais S9, S19, S20, S22 e S23 foram selecionados para a triagem secundária. A atividade máxima contra E. coli e S. aureus foi registrada pelo isolado bacteriano S19, ou seja, zonas de inibição de 6,5 mm e 9 mm, enquanto S20 mostrou zonas de 7,5 mm e 6 mm, respectivamente. A identificação molecular foi realizada com base na análise da sequência 16S rRNA. Finalmente, os isolados foram identificados como B. cereus número de acesso LC538271 e K. pneumoniae número de acesso MT078679. A análise do extrato bacteriano S20 por meio de GC-MS indicou a presença de oito compostos de natureza e estrutura diversas. O presente estudo sugere que resíduos da indústria farmacêutica e de ração para aves podem conter bactérias produtoras de antibióticos. Essas bactérias podem ser utilizadas para a produção de antibióticos B. cereus e K. pneumoniae isolados de resíduos de rações de aves e indústrias farmacêuticas têm potencial para produzir antibióticos e podem ser usados ​​para controlar o crescimento microbiano.


Assuntos
Humanos , Staphylococcus aureus , Resíduos Industriais , RNA Ribossômico 16S , Extratos Vegetais , Testes de Sensibilidade Microbiana , Escherichia coli , Cromatografia Gasosa-Espectrometria de Massas , Antibacterianos/farmacologia
2.
J Agric Food Chem ; 70(31): 9722-9729, 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35913050

RESUMO

Southern mountain mint, Pycnanthemum pycnanthemoides (Leavenw.) Fernald, is a mountain mint species endemic to the southeastern United States. The odorants responsible for the plant's odor have not been previously characterized. In this study, 28 odorants were identified in a high-vacuum distillate of P. pycnanthemoides employing gas chromatography-olfactometry and gas chromatography-mass spectrometry. Flavor dilution (FD) factors were determined by aroma extract dilution analysis. Ten odorants with FD factors ≥16 were quantitated by stable isotope dilution assays, odor activity values (OAVs) were calculated, and the stereochemistry of chiral odorants was determined. Odorants with OAV ≥1 included ß-ionone (floral, violet; OAV 310), piperitenone (mint; OAV 100), piperitone (mint; OAV 87), linalool (floral, citrus; OAV 45), myrcene (terpeny; OAV 35), (R)-(+)-pulegone (mint, medicinal; OAV 18), (2S,5R)-(-)-menthone (mint, fresh; OAV 6.6), and 1,8-cineole (eucalyptus; OAV 4.0). An odor simulation model based on the quantitative analysis was a close match to the sensory attributes of an aqueous infusion of dried P. pycnanthemoides. The study's results establish insights into the complex odor profile of P. pycnanthemoides and provide a foundation for future studies on the odor variability within P. pycnanthemoides and other species of the Pycnanthemum genus.


Assuntos
Lamiaceae , Mentha , Compostos Orgânicos Voláteis , Aromatizantes/química , Cromatografia Gasosa-Espectrometria de Massas , Odorantes/análise , Olfatometria , Compostos Orgânicos Voláteis/química
3.
Anal Chim Acta ; 1221: 340159, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35934385

RESUMO

In this study, a cooling assisted solid-phase microextraction technique (CA-SPME) was proposed and used for identifying volatile and semi-volatile compounds in edible oil innovatively coupled to gas chromatography-mass spectrometry. Compared with regular SPME technique, CA-SPME presented significantly higher extraction efficiencies for analytes in edible oil due to its synergistic effect of heating and cooling. After optimization of the extraction conditions including heating temperature, cooling temperature, extraction time, and added amount of edible oil, thirty-eight, thirty-six, twenty-nine, and thirty-three kinds of compounds in peanut oil, olive oil, canola oil, and soybean oil were successfully identified, respectively, using DVB/CAR/PDMS coating with extraction time of 30 min and edible oil amounts of 20 µL. Principal component analysis, partial least squares discriminant analysis, and hierarchical clustering analysis (HCA) were performed to evaluate the potential of proposed method in discriminating edible oils adulteration (peanut oil adulterated with canola oil, peanut oil adulterated with soybean oil, olive oil adulterated with canola oil) subsequently. Results demonstrated that the method was useful in successful discrimination of pure and adulterated edible oils with adulteration percentages ranging from 0.5 to 10%. Furthermore, volatiles contributing to classifications between pure and adulterated edible oils were also illustrated based on variable importance for the projection analysis and distributions of volatiles in HCA heatmaps. The proposed method provided a novel strategy for sensitive detection of edible oil adulteration without any other sample pretreatment.


Assuntos
Microextração em Fase Sólida , Óleo de Soja , Cromatografia Gasosa-Espectrometria de Massas , Azeite de Oliva/análise , Óleos Vegetais/análise , Microextração em Fase Sólida/métodos , Óleo de Soja/análise
4.
Anal Chim Acta ; 1221: 340176, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35934390

RESUMO

Lipid peroxidation products, such as short chain aldehydes, are powerful biomarkers of oxidative stress, due to the advantage of long lifetime compared to other metabolites of the lipidome. This work proposes an advanced combined derivatization/solvent-less extraction procedure from plasma followed by rapid Gas Chromatography with Mass Spectrometric detection (GC-MS). A new sample pretreatment protocol is presented which is based on a combination of aldehyde derivatization with methoxyamine under fully aqueous-based conditions of diluted plasma samples followed by headspace solid-phase microextraction (HS-SPME) which is faster compared to methods in the literature serving the same purpose. Being the smallest oximation reagent, methoxyamine derivatization does not require a silylation step of hydroxyl groups as customary and made it possible to have the shortest run times for this series of aldehydes by GC-MS. A Response Surface Methodology (RSM) is employed to optimize the HS-SPME of the aldehyde methoximes to provide insights into the Design Space (DS) of HS-SPME of aldehydes of variable chain lengths and unsaturation. The workflow includes a Quality by Design (QbD) approach for optimization of sample microextraction and derivatization methodology under fully aqueous conditions, in contrast to all reported non-aqueous tedious and long extraction methods in the literature followed by development of a rapid GC-MS assay. The optimal sample preparation obtained from the RSM, and multiple linear regression procedure involved addition of 15 mg methoxyamine (CH3ONH2) and 160 mg Na2SO4 to 0.5 mL plasma diluted to 1 mL with water in an extraction vial followed by HS-SPME using Polydimethylsiloxane/Divinylbenzene fiber at 750 rpm and 77 °C for 15 min. The developed HS-SPME-GC-MS method was validated according to FDA guidelines in SIM mode and applied for targeted determination of lipid peroxidation aldehyde metabolites in plasma of 24 cardiovascular patients vs 20 healthy controls. The run time of the GCMS method was less than 15 min and the LOQ of the 10 targeted aldehydes were 0.5 nM for decanal, 5 nM for hexanal, heptanal, octanal, citronellal and citral, 7 nM for malondialdehyde, 35 nM for 4- hydroxynonenal, 105 nM for 4- hydroxyhexenal and 500 nM for glyoxal. Hexanal, Malondialdehyde and Hydroxynonenal concentrations were significantly higher in patients (p-value<0.05) in the targeted study, while citral was significantly lower as obtained from the untargeted study. Reporting an aldehydic profile signature -whether predictive or diagnostic-for cardiovascular patients would support proper medical intervention at the initiation or progression phases of the disease when expanded on larger number of subjects.


Assuntos
Aldeídos , Microextração em Fase Sólida , Aldeídos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Malondialdeído , Metabolômica , Microextração em Fase Sólida/métodos
5.
Anal Chim Acta ; 1222: 340039, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35934427

RESUMO

Ion mobility spectrometry (IMS) is gaining importance in the field of food safety and authenticity in recent years due to its main potential to overcome the challenges that arise from the complexity of food matrices. For many years, IMS has been used as a stand-alone analytical detector due to its quick response, high sensitivity, and portability, and stand-alone applications in food analysis have been explored in recent years. At the same time, IMS hyphenation to mass spectrometry (MS) techniques, usually combined with liquid or gas chromatography (LC/GC), provides an additional dimension to separate isobaric compounds and thus improves method selectivity. Besides, with such ion mobility - mass spectrometry (IM-MS) methods, background noise decreases, increasing method sensitivity, and it provides complementary information to mass spectra and retention time with the collision cross section (CCS). The development of CCS databases within the food safety field would even permit the identification of compounds in non-targeted approaches. Furthermore, it would increase the confidence of control laboratories when determining a sample as non-compliant. Therefore, the number of applications by IMS on food safety and authenticity has increased remarkably in recent years. This review provides the general insights of IMS with the current state and recent approaches for its performance improvement and a general outlook of its applicability in food safety and authenticity.


Assuntos
Inocuidade dos Alimentos , Espectrometria de Mobilidade Iônica , Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Mobilidade Iônica/métodos , Espectrometria de Massas/métodos
6.
Anal Chim Acta ; 1222: 340171, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35934429

RESUMO

Nontarget analysis enables high-efficiency screening and identification of halogenated organic pollutants (HOPs) in complex matrices irrespective of lacking authentic standards, particularly for novel and emerging species, thereby realizing comprehensive component characterization of HOPs. Notwithstanding, nontarget analysis and comprehensive characterization of HOPs remain on the way to improvement. In this study, we implemented nontarget analysis of HOPs in fly ash, egg and sediment using gas chromatography quadrupole-orbitrap high-resolution mass spectrometry with the aid of chromatogram segmentation and Cl/Br-specific screening algorithms, and further performed comprehensive characterization of components and distribution of HOPs. In total, 122 HOP formulas were identified and tentatively assigned with structures, of which 28 were found in ≥ two matrices. Taking isomers into account, in total 1059 HOP congeners were found. Based on the identification and semiquantification results, the chemical components and concentration profiles of HOPs were preliminarily clarified, and accordingly the overall pollution signatures of HOPs were sketched. The total concentrations of HOPs in the fly ash, egg and sediment were 4.7, 41.2 and 750.8 µg g-1, respectively. Organochlorines were the most abundant among the categories classified by halogen types, and halogenated benzenes, halogenated dioxins, halogenated biphenyls/terphenyls and halogenated polycyclic aromatic hydrocarbons (H-PAHs) were the predominant of the structurally classified categories. Moreover, dozens of formulas of novel/little-known HOPs such as mix-chlorinated/brominated PAHs with ≥4 aromatic rings and polychlorinated terphenyls were identified. This study presents an accurate and high-performance nontarget analysis method for HOPs in complex matrices, and yields new cognitions on the pollution status of HOPs from an overall perspective.


Assuntos
Poluentes Ambientais , Hidrocarbonetos Policíclicos Aromáticos , Algoritmos , Cinza de Carvão/análise , Poluentes Ambientais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise
7.
Molecules ; 27(15)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35956746

RESUMO

Among various volatile organic compounds (VOCs) emitted from human skin, trans-2-nonenal, benzothiazole, hexyl salicylate, α-hexyl cinnamaldehyde, and isopropyl palmitate are key indicators associated with the degrees of aging. In our study, extraction and determination methods of human body odor are newly developed using headspace-in needle microextraction (HS-INME). The adsorbent was synthesized with graphene oxide:polyaniline/zinc nanorods/zeolitic imidazolate framework-8 (GO:PANI/ZNRs/ZIF-8). Then, a wire coated with the adsorbent was placed into the adsorption kit to be directly exposed to human skin as in vivo sampling and inserted into the needle so that it was able to be desorbed at the GC injector. The adsorption kit was made in-house with a 3D printer. For the in vitro method, the wire coated with the adsorbent was inserted into the needle and exposed to the headspace of the vial. When a cotton T-shirt containing body odor was transferred to a vial, the headspace of the vial was saturated with body odor VOCs. After volatile organic compounds were adsorbed in the dynamic mode, the needle was transferred to the injector for analysis of the volatile organic compounds by gas chromatography/mass spectrometry (GC/MS). The conditions of adsorbent fabrication and extraction for body odor compounds were optimized by response surface methodology (RSM). In conclusion, it was able to synthesize GO:PANI/ZNRs/ZIF-8 at the optimal condition and applicable to both in vivo and in vitro methods for body odor VOCs analysis.


Assuntos
Compostos Orgânicos Voláteis , Odor Corporal , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Odorantes/análise , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise
8.
Molecules ; 27(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35956782

RESUMO

The quality of Radix Bupleuri is greatly affected by its growing environment. In this study, Radix Bupleuri samples that were harvested from seven different regions across northwest China were examined by high-performance liquid chromatography (HPLC) and gas chromatography (GC) coupled with mass spectrometry (MS) to reveal significant differences in quality contributed by the cultivation region. An HPLC-MS method was firstly established and used in the multiple reaction monitoring mode for the quantitative analysis of five saikosaponins in Radix Bupleuri so as to evaluate the difference in the absolute content of saikosaponins attributable to the cultivation region. The effect on the components of Radix Bupleuri was further investigated based on the profiles of the representative saponins and volatile compounds, which were extracted from the Radix Bupleuri samples and analyzed by HPLC-MS and GC-MS. Multivariate statistical analysis was employed to differentiate the Radix Bupleuri samples cultivated in different regions and to discover the differential compositions. The developed quantitative method was validated to be accurate, stable, sensitive, and repeatable for the determination of five saikosaponins. Further statistical tests revealed that the collected Radix Bupleuri samples were distinctly different from each other in terms of both saponins and volatile compounds, based on the provinces where they were grown. In addition, twenty-eight saponins and fifty-eight volatile compounds were identified as the differentially accumulated compositions that contributed to the discrimination of the Radix Bupleuri samples. The Radix Bupleuri samples grown in Shouyang county showed the highest content of saikosaponins. All of the results indicated that the cultivation region significantly affected the accumulation and diversity of the main chemical components of Radix Bupleuri. The findings of this research provide insights into the effect of the cultivation region on the quality of Radix Bupleuri and the differentiation of Radix Bupleuri cultivated in different regions based on the use of HPLC-MS and GC-MS combined with multivariate statistical analysis.


Assuntos
Bupleurum , Medicamentos de Ervas Chinesas , Saponinas , Bupleurum/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas , Saponinas/análise
9.
Molecules ; 27(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35956795

RESUMO

Organotin compounds (OTCs) are among the most hazardous substances found in the marine environment and can be determined by either the ISO 23161 method based on extraction with non-polar organic solvents and gas chromatography analysis or by the recently developed QuEChERS method coupled to liquid chromatography-mass spectrometry (LC-MS/MS). To date, the QuEChERS LC/MS and ISO 23161 methods have not been compared in terms of their fit-for-purpose and reliability in the determination of OTCs in bottom sediments. In the case of ISO 23161, due to a large number of interferences gas chromatography-mass spectrometry was not suitable for the determination of OTCs contrary to more selective determination by gas chromatography with an atomic emission detector. Moreover, it has been found that the derivatization of OTCs to volatile compounds, which required prior gas chromatography determination, was strongly affected by the sediments' matrices. As a result, a large amount of reagent was needed for the complete derivatization of the compounds. Contrary to ISO 23161, the QuEChERS LC-MS/MS method did not require the derivatization of OTC and is less prone to interferences. Highly volatile and toxic solvents were not used in the QuEChERS LC-MS/MS method. This makes the method more environmentally friendly according to the principles of green analytical chemistry. QuEChERS LC-MS/MS is suitable for fast and reliable environmental monitoring of OTCs in bottom sediments from the Odra River estuary. However, determination of di- and monobutyltin by the QuEChERS LC-MS/MS method was not possible due to the constraints of the chromatographic system. Hence, further development of this method is needed for monitoring di- and monobutyltin in bottom sediments.


Assuntos
Compostos Orgânicos de Estanho , Rios , Cromatografia Líquida , Monitoramento Ambiental/métodos , Estuários , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos de Estanho/análise , Reprodutibilidade dos Testes , Rios/química , Solventes/análise , Espectrometria de Massas em Tandem
10.
Molecules ; 27(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35956894

RESUMO

The Japanese pepper (Zanthoxylum piperitum DC.) is an attractive plant that is highly palatable and benefits human health. There are several lineages of pepper plants in Japan. However, the classification of each lineage by analyzing its volatile compounds and studies on the effects of differences in volatile compounds on human flavor perception have not been performed in detail. Herein, we conducted gas chromatography (GC) and GC/mass spectrometry (GC/MS) analysis of volatile compounds and sensory evaluation of flavor by an analytical panel using 10 commercially available dry powdered Japanese pepper products from different regions. GC and GC/MS analysis detected limonene, ß-phellandrene, citronellal, and geranyl acetate as the major volatile compounds of Japanese peppers. The composition of volatile compounds showed different characteristics depending on the growing regions, and cluster analysis of composition classified the products into five groups. The sensory evaluation classified the products into four groups, and the results of both classifications were in good agreement. Our results provide an important basis for proposing cooking and utilization methods that take advantage of the unique characteristics of each lineage based on scientific evidence.


Assuntos
Piper nigrum , Compostos Orgânicos Voláteis , Zanthoxylum , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Japão , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Zanthoxylum/química
11.
Molecules ; 27(15)2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35956905

RESUMO

Grumixama (Eugenia brasiliensis Lam.) is a native fruit of the Brazilian Atlantic Forest, belonging to the Myrtaceae family, which designatesthe most significant number of species with food potential. It stands out due to its phytochemical characteristics because of the presence of polyphenols and volatile organic compounds. Volatile compounds are substances released by foods that give off an aroma and influence flavor. Solid-phase microextraction is a technique that allows for low-cost, fast, and solvent-free extraction, has an affinity for numerous analytes, and is easily coupled to gas chromatography. The objectives of this work were to evaluate the efficiency of different fibers of SPME (solid-phase microextraction) in the extraction of volatile organic compounds from grumixama pulp; optimize a method for extraction time, temperature, and sample weight; and to determine the characteristic volatile profile of this fruit. For the extraction of volatile compounds, three fibers of different polarities were used: polar polyacrylate (PA) fibers, divinylbenzene/carboxyne/polydimethylsiloxane (DVB/CAR/PDMS) semipolar fibers, and polydimethylsiloxane/divinylbenzene (PDMS/DVB). Fourteen volatile organic compounds (VOCs) were identified by DVB/CAR/PDMS, six by PA, and seven by PDMS/DVB through solid-phase microextraction in the headspace mode (SPME-HS). Considering the total number of compounds identified, regardless of the fiber used, and the optimization of the method, Eugenia brasiliensis presented sesquiterpene fractions (85.7%, 83.3%, and 85.7% of total VOCs) higher than the monoterpene fractions (14.3%, 16.7%, and 14.3%) for DVB/CAR/PDMS, PA, and PDMS/DVB, respectively in its composition. In addition, it was possible to verify that the fiber DVB/CAR/PDMS presented a better efficiency due to the larger chromatographic area observed when the grumixama pulp was subjected to conditions of 75 °C, 2.0 g, and an adsorption time of 20 min.


Assuntos
Eugenia , Compostos Orgânicos Voláteis , Dimetilpolisiloxanos/química , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise
12.
Molecules ; 27(15)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35956929

RESUMO

A new, simple and sensitive method for isolating nine compounds from the bisphenol group (analogues: A, B, C, E, F, G, Cl2, Z, AP) based on one-step liquid-liquid microextraction with in situ acylation followed by gas chromatography-mass spectrometry was developed and validated using influent and effluent wastewaters. The chemometric approach based on the Taguchi method was used to optimize the main conditions of simultaneous extraction and derivatization. The recoveries of the proposed procedure ranged from 85 to 122%, and the repeatability expressed by the coefficient of variation did not exceed 8%. The method's limits of detection were in the range of 0.4-64 ng/L, and the method's limits of quantification ranged from 1.3 to 194 ng/L. The developed method was used to determine the presence of the tested compounds in wastewater from a municipal wastewater treatment plant located in northeastern Poland. From this sample, eight analytes were detected. Concentrations of bisphenol A of 400 ng/L in influent and 100 ng/L in effluent were recorded, whereas other bisphenols reached 67 and 50 ng/L for influent and effluent, respectively. The removal efficiency of bisphenol analogues in the tested wastewater treatment plant ranged from 7 to approximately 88%.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Compostos Benzidrílicos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Fenóis , Águas Residuárias/química , Água/análise , Poluentes Químicos da Água/análise
13.
Molecules ; 27(15)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35956948

RESUMO

Dryopteris crassirhizoma Nakai is a Chinese traditional medicinal fern plant for heat-clearing and detoxifying, promoting blood circulation and dissipating blood stasis. Previous researches showed that many factors could influence the components of medicinal plants, and the plant part is one of the main factors. So far, only the underground part of D. crassirhizoma, called "Mianma Guanzhong", has been widely sold in the market. However, the above-ground part was usually at low utilization, resulting in a waste of medicinal resources. In order to further develop and utilize the medicinal resources of D. crassirhizoma, the constituents, total flavonoid contents and antioxidant activity of the above-ground and underground parts of D. crassirhizoma were tentatively analyzed and compared based on HS-SPME-GC-MS and UPLC/Q-TOF-MS. The results showed that (1) the volatile components were mainly focused in the above-ground part of D. crassirhizoma, including 3-carene, isoledene, ionene, 4-amino-1-naphthol and furfural. (2) Nonvolatile components of the underground part of D. crassirhizoma contained phenolic acid, flavonoids, phloroglucinol and less fatty acid. (3) The common compounds of the above-ground and underground parts of D. crassirhizoma were phenolic acid and flavaspidic acid AB. (4) Antioxidant activity of the underground part was stronger than that of the above-ground part of D. crassirhizoma. In conclusion, both the above-ground and underground parts of D. crassirhizoma are important medicinal resources worthy of further development.


Assuntos
Dryopteris , Antioxidantes , Flavonoides , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Sólida
14.
Molecules ; 27(15)2022 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-35956972

RESUMO

Bladder cancer is one of most common types of cancer diagnosed in the genitourinary tract. Typical tests are costly and characterized by low sensitivity, which contributes to a growing interest in volatile biomarkers. Head space solid phase microextraction (SPME) was applied for the extraction of volatile organic compounds from urine samples, and gas chromatography time of flight mass spectrometry (GC×GC TOF MS) was used for the separation and detection of urinary volatiles. A cohort of 40 adult patients with bladder cancer and 57 healthy persons was recruited. Different VOC profiles were obtained for urine samples taken from each group. Twelvecompounds were found only in the samples from theBC group.The proposed candidate biomarkers are butyrolactone; 2-methoxyphenol; 3-methoxy-5-methylphenol; 1-(2,6,6-trimethylcyclohexa-1,3-dien-1-yl)-2-buten-1-one; nootkatone and 1-(2,6,6-trimethyl-1-cyclohexenyl)-2-buten-1-one.Since most of the studies published in the field are proving the potential of VOCs detected in urine samples for the screening and discrimination of patients with bladder cancer from healthy, but rarely presenting the identity of proposed biomarkers, our study represents a novel approach.


Assuntos
Neoplasias da Bexiga Urinária , Compostos Orgânicos Voláteis , Adulto , Biomarcadores , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Doenças Raras , Microextração em Fase Sólida/métodos , Neoplasias da Bexiga Urinária/diagnóstico , Compostos Orgânicos Voláteis/análise
15.
Sensors (Basel) ; 22(15)2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35957445

RESUMO

The realization of an unobtrusive and effective technology able to track fish freshness in real time and inform on its edibility is highly demanded, but still unachieved. In the present paper, we address this issue through a single metal oxide gas sensor working in temperature modulation mode. The system can work without an external reference air source, which is an appealing feature for its possible integration in domestic refrigerators. Tests were carried out using fresh sea bream fillets as case study and working both inside the refrigerator and at room temperature. Parallel gas chromatography-mass spectrometry and microbiological characterization indicated the marked dependence of both the microbiological condition and the gas-phase composition from the individual sample and from the storage temperature. Despite such a large variability, which may be expected in real applications, the proposed system provided similar responses whenever the total bacterial population approached and exceeded the edibility threshold of 107 CFU/g.


Assuntos
Dourada , Animais , Bactérias , Cromatografia Gasosa-Espectrometria de Massas , Óxidos , Temperatura
16.
Food Res Int ; 159: 111585, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35940759

RESUMO

In this work, the feasibility of combining headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC/MS) with colorimetric sensor array (CSA) for flavor characterization of Zhenjiang aromatic vinegar (ZAV) from different grades was evaluated. Firstly, a new type of nanocomposite CSA that combines porous nanomaterials including hollow zeolitic imidazolate framework-8 (H-ZIF-8) and Universitetet i Oslo-66-NO2 (UiO-66-NO2) with chemically responsive dyes was successfully constructed. Then, the nanocomposite CSA was applied to effectively discriminate ZAV of different grades and further quantitively predict the characteristic aroma components by using multivariate data analysis. Compared with other pattern recognition methods, support vector machine (SVM) model achieved the highest recognition rate both for training set (100%) and prediction set (94.44%). Furthermore, a good performance of quantitative prediction of characteristic aroma components of ZAV including acetic acid, total volatile acids, furfural, aldehyde ketones, ethyl acetate and esters combining CSA with partial least square (PLS) regression was achieved with all the correlation coefficients being over 0.80 for training and prediction sets. Therefore, the nanocomposite CSA combined with chemometrics could be an effective tool for the rapid and nondestructive assessment of flavor and quality of vinegar.


Assuntos
Nanocompostos , Compostos Orgânicos Voláteis , Ácido Acético/análise , Colorimetria , Cromatografia Gasosa-Espectrometria de Massas/métodos , Estruturas Metalorgânicas , Dióxido de Nitrogênio , Ácidos Ftálicos , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise
17.
J Mass Spectrom ; 57(8): e4876, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35941810

RESUMO

In this work, the isolation step in the linear ion trap was performed using different "q values" conditions at a low collision-induced dissociation (CID) energy leading to the parent ion resolution improvements, reasonably due to better ion energy distribution. According to the results, we obtained a greater resolution and mass accuracy operating in both traditional electrospray and low voltage ionization near the q value = 0.778 and with a CID energy of 10%. This effect was evaluated with low-molecular-mass compounds (skatole and arginine). The proposed optimization yielded a superior instrument performance without adding technological complexity to mass spectrometry analyses.


Assuntos
Espectrometria de Massas por Ionização por Electrospray , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas por Ionização por Electrospray/métodos
18.
Int J Mol Sci ; 23(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35955459

RESUMO

Obesity is associated with a pro-inflammatory and pro-thrombotic state that supports atherosclerosis progression and platelet hyper-reactivity. During the last decade, the platelet lipidome has been considered a treasure trove, as it is a source of biomarkers for preventing and treating different pathologies. The goal of the present study was to determine the lipid profile of platelets from non-diabetic, severely obese patients compared with their age- and sex-matched lean controls. Lipids from washed platelets were isolated and major phospholipids, sphingolipids and neutral lipids were analyzed either by gas chromatography or by liquid chromatography coupled to mass spectrometry. Despite a significant increase in obese patient's plasma triglycerides, there were no significant differences in the levels of triglycerides in platelets among the two groups. In contrast, total platelet cholesterol was significantly decreased in the obese group. The profiling of phospholipids showed that phosphatidylcholine and phosphatidylethanolamine contents were significantly reduced in platelets from obese patients. On the other hand, no significant differences were found in the sphingomyelin and ceramide levels, although there was also a tendency for reduced levels in the obese group. The outline of the glycerophospholipid and sphingolipid molecular species (fatty-acyl profiles) was similar in the two groups. In summary, these lipidomics data indicate that platelets from obese patients have a unique lipid fingerprint that may guide further studies and provide mechanistic-driven perspectives related to the hyperactivate state of platelets in obesity.


Assuntos
Lipidômica , Fosfolipídeos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Obesidade , Esfingolipídeos , Triglicerídeos
19.
Int J Mol Sci ; 23(15)2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35955586

RESUMO

We studied the efficiency of three culture series of the microalgae Phaeodactylum tricornutum (P. tricornutum) and bacteria Thalassospira sp. (axenic microalgae, bacterial culture and co-culture of the two) in removing bisphenols (BPs) from their growth medium. Bacteria were identified by 16S ribosomal RNA polymerase chain reaction (16S rRNA PCR). The microorganism growth rate was determined by flow cytometry. Cultures and isolates of their small cellular particles (SCPs) were imaged by scanning electron microscopy (SEM) and cryogenic transmission electron microscopy (Cryo-TEM). BPs were analyzed by gas chromatography coupled with tandem mass spectrometry (GC-MS/MS). Our results indicate that some organisms may have the ability to remove a specific pollutant with high efficiency. P. tricornutum in axenic culture and in mixed culture removed almost all (more than 99%) of BPC2. Notable differences in the removal of 8 out of 18 BPs between the axenic, mixed and bacterial cultures were found. The overall removals of BPs in axenic P. tricornutum, mixed and bacterial cultures were 11%, 18% and 10%, respectively. Finding the respective organisms and creating microbe societies seems to be key for the improvement of wastewater treatment. As a possible mediating factor, numerous small cellular particles from all three cultures were detected by electron microscopy. Further research on the mechanisms of interspecies communication is needed to advance the understanding of microbial communities at the nano-level.


Assuntos
Diatomáceas , Microalgas , Rhodospirillaceae , Bactérias/genética , Meios de Cultivo Condicionados , Diatomáceas/genética , Cromatografia Gasosa-Espectrometria de Massas , RNA Ribossômico 16S/genética , Espectrometria de Massas em Tandem
20.
Anal Chem ; 94(31): 11096-11103, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35912800

RESUMO

Per- and polyfluoroalkyl substances (PFASs) have been widely used since the 1940s in industry and everyday household products. They also persist in the environment and bioaccumulate in humans and wildlife. Despite these concerns, the identities of most PFASs in environmental and biological samples are unknown. Herein, we describe a novel cyclic ion mobility mass spectrometer (cIMS), hyphenated with gas chromatography (GC) atmospheric pressure chemical ionization, that can reveal the presence of unknown PFASs on the basis of the ratio of their mass and collision cross section (CCS). Prediction of the CCS of ca. 20,000 chemicals used in industry and commerce indicates that most compounds characterized by CCS values that are less than the sum of 100 Å2 and one-fifth of their mass are either PFASs or polybrominated flame retardants. When this filter is applied to GC-cIMS data collected from a set of 20 indoor dust samples, PFAS compounds are revealed without prior knowledge of their occurrence. Validation of this approach was performed using SRM 2585, a standard reference material of household dust, by comparing the PFASs detected with those (tentatively) identified in previous studies. Chlorofluoro phthalimides tentatively identified previously were confirmed with a synthesized standard. The method also reveals the presence of chlorofluoro n-alkanes as an emerging class of "forever chemicals" that contaminate the indoor environment.


Assuntos
Fluorcarbonetos , Cromatografia Líquida , Poeira/análise , Fluorcarbonetos/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espectrometria de Massas
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